阅读说明：本技术 一种云梯车专用平衡阀组、液压控制系统及其控制方法 (Special balance valve set for aerial ladder vehicle, hydraulic control system and control method of special balance valve set ) 是由 于装 于 2021-02-08 设计创作，主要内容包括：本发明提供一种云梯车专用平衡阀组、液压控制系统及其控制方法,云梯车专用平衡阀组括阀体,所述阀体集成旁通单向阀、平衡阀和梭阀；所述阀体开设第1油口、第2油口、第1负载口和第2负载口；平衡阀包括并联的先导控制阀和单向阀；所述先导控制阀的先导控制口连通到所述第2分支口。本发明提供的一种云梯车专用平衡阀组、液压控制系统及其控制方法,可实现负载到位或者落地后,卷扬液压马达回路被特殊设计的旁通单向阀及时旁通并停止转动,从而避免与液压马达相连的卷筒空转引起钢丝绳松动、缠绕等问题,保证卷筒使用的安全性和可靠性。(The invention provides a special balance valve group for an aerial ladder vehicle, a hydraulic control system and a control method of the special balance valve group, wherein the special balance valve group for the aerial ladder vehicle comprises a valve body, and the valve body is integrated with a bypass one-way valve, a balance valve and a shuttle valve; the valve body is provided with a1 st oil port, a2 nd oil port, a1 st load port and a2 nd load port; the balance valve comprises a pilot control valve and a one-way valve which are connected in parallel; and a pilot control port of the pilot control valve is communicated with the 2 nd branch port. According to the special balance valve group for the aerial ladder vehicle, the hydraulic control system and the control method thereof, the winding hydraulic motor loop can be timely bypassed by the specially designed bypass check valve and stops rotating after the load is in place or falls to the ground, so that the problems of looseness, winding and the like of a steel wire rope caused by idling of a winding drum connected with a hydraulic motor are avoided, and the use safety and reliability of the winding drum are ensured.)

1. The special balance valve bank for the aerial ladder vehicle is characterized by comprising a valve body (1), wherein the valve body (1) is integrated with a bypass one-way valve (2), a balance valve (3) and a shuttle valve (4); the valve body (1) is provided with a1 st oil port (V1), a2 nd oil port (V2), a1 st load port (C1) and a2 nd load port (C2);

the 1 st oil port (V1) and the 2 nd oil port (V2) are both used for being connected to an oil supply reversing valve (5); the 1 st load port (C1) is used for being connected to a1 st motor port (D1) of a hydraulic motor; the 2 nd load port (C2) is used for being connected to a2 nd motor port (D2) of a hydraulic motor;

a1 st oil path is formed between the 1 st oil port (V1) and the 1 st load port (C1); a1 st branch port (A1), a2 nd branch port (A2) and A3 rd branch port (A3) are sequentially arranged on the 1 st oil passage in a direction from the 1 st oil port (V1) to the 1 st load port (C1);

a2 nd oil path is formed between the 2 nd oil port (V2) and the 2 nd load port (C2); a 4 th branch port (B1), the balance valve (3), and a 5 th branch port (B2) are provided in the 2 nd oil line in this order from the 2 nd port (V2) to the 2 nd load port (C2);

the 1 st oil inlet of the shuttle valve (4) is communicated with the 1 st branch port (A1); the 2 nd oil inlet of the shuttle valve (4) is communicated with the 4 th branch port (B1); the oil outlet (X) of the shuttle valve (4) is used for being connected to a motor brake port (6);

the oil inlet of the bypass one-way valve (2) is communicated with the 3 rd branch port (A3); an oil outlet of the bypass check valve (2) is communicated with the 5 th branch port (B2), the direction of the bypass check valve (2) from the 3 rd branch port (A3) to the 5 th branch port (B2) is a conducting direction, and the direction of the bypass check valve (2) from the 5 th branch port (B2) to the 3 rd branch port (A3) is a closing direction;

the balance valve (3) comprises a pilot control valve (31) and a one-way valve (32) which are connected in parallel; a pilot control port of the pilot control valve (31) is communicated with the 2 nd branch port (A2).

2. The hydraulic control system based on the aerial ladder vehicle special balance valve bank of claim 1 is characterized by comprising the aerial ladder vehicle special balance valve bank, an oil supply reversing valve (5), a hydraulic motor (7), a winding drum (8) and a load (9);

the hydraulic driving end of the hydraulic motor (7) is connected with the winding drum (8) and is used for driving the winding drum (8) to rotate; one end of the load (9) is wound on the winding drum (8) through a steel wire rope;

the oil supply reversing valve (5) is communicated with a1 st oil port (V1) and a2 nd oil port (V2) of the aerial ladder vehicle special balance valve group; the oil supply reversing valve (5) is provided with three gears which are a forward gear, a reverse gear and a stop gear respectively; when the oil supply reversing valve (5) is reversed to a stop gear position, oil is not supplied to the 1 st oil port (V1) and the 2 nd oil port (V2); when the oil supply reversing valve (5) is reversed to a forward gear, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with the 2 nd oil port (V2) and is used for conveying hydraulic oil to the 2 nd oil port (V2); the return oil from the 1 st oil port (V1) is communicated to the oil return end (T) of the oil supply reversing valve (5); when the oil supply reversing valve (5) is reversed to a reverse gear, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with the 1 st oil port (V1) and is used for conveying hydraulic oil to the 1 st oil port (V1); the return oil passing through the 2 nd oil port (V2) is communicated to the oil return end (T) of the oil supply reversing valve (5);

an oil outlet (X) of a shuttle valve (4) of the aerial ladder vehicle special balance valve group is connected to a motor brake port (6);

the 1 st load port (C1) of the aerial ladder vehicle special balance valve bank is connected to the 1 st motor oil port (D1) of the hydraulic motor (7); the 2 nd load port (C2) is connected to the 2 nd motor port (D2) of the hydraulic motor (7);

the opening pressure of the bypass one-way valve (2) is smaller than the no-load starting pressure of the hydraulic motor (7).

3. The hydraulic control method of the aerial ladder vehicle special balance valve group-based hydraulic control system as claimed in claim 2, characterized by comprising the following steps:

step 1, a hydraulic motor (7) drives a winding drum (8) to rotate in the positive direction, and then drives a load (9) to rise under the working condition, and the method comprises the following steps:

step 1.1, operating the oil supply reversing valve (5) to enable the oil supply reversing valve (5) to shift to a forward gear, wherein at the moment, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with a2 nd oil port (V2), and conveying hydraulic oil to the 2 nd oil port (V2);

step 1.2, the hydraulic oil flows to a 4 th branch port (B1) after passing through a2 nd oil port (V2), and the 4 th branch port (B1) is divided into two paths of hydraulic oil:

the first path of hydraulic oil enters the interior of the shuttle valve (4) through a2 nd oil inlet of the shuttle valve (4), pushes a valve core of the shuttle valve (4) from right to left, pushes the valve core of the shuttle valve (4) to the left, closes a1 st oil inlet of the shuttle valve (4), blocks a1 st branch port (A1) from supplying oil to a1 st oil inlet of the shuttle valve (4), and simultaneously opens an oil outlet (X) of the shuttle valve (4), so that the first path of hydraulic oil flows out of the oil outlet (X) of the shuttle valve (4), flows into a motor brake cavity through a motor brake port (6), and further opens a motor brake;

meanwhile, for the second path of hydraulic oil, because the 2 nd oil port (V2) is communicated with the hydraulic oil delivery end (P) of the oil supply reversing valve (5), and the 1 st oil port (V1) is communicated with the oil return end (T) of the oil supply reversing valve (5), the oil pressure of the 2 nd oil path between the 2 nd oil port (V2) and the 2 nd load port (C2) is higher than the oil pressure of the 1 st oil path between the 1 st oil port (V1) and the 1 st load port (C1), therefore, the pilot control port of the balance valve (3) is a low pressure end, the pilot control valve (31) is closed, the second path of hydraulic oil flows to the 5 th branch port (B2) through the check valve (32) of the balance valve (3), the direction from the 5 th branch port (B2) to the 1 st oil port (V1) of the bypass check valve (2) is in a closed state, therefore, the second path of hydraulic oil directly flows out from the 2 nd load port (C2) after passing through the 5 th branch port (B2), then flows into a hydraulic motor cavity through a motor oil port (D2) of the 2 nd so as to drive the hydraulic motor (7) to rotate forwards; the hydraulic motor (7) rotates forwards, so that the winding drum (8) is driven to rotate forwards, and the load (9) is driven to ascend;

the return oil of the hydraulic motor flows out from a1 st motor oil port (D1) and flows into A3 rd branch port (A3) from a1 st load port (C1); at the 3 rd branch port (A3), the oil return pressure of the 3 rd branch port (A3) is far lower than the oil supply pressure of the 5 th branch port (B2), so that the bypass check valve (2) is in a closed state;

after passing through the 3 rd branch port (A3), the hydraulic motor return oil flows to the 2 nd branch port (A2), and the pilot control valve (31) is in a closed state because the 2 nd branch port (A2) is a low-pressure end;

after passing through the 2 nd branch port (A2), the hydraulic motor return oil flows to the 1 st branch port (A1), and because the 1 st branch port (A1) is a low-pressure end and the pressure is far less than the pressure of the 4 th branch port (B1), the 1 st oil inlet of the shuttle valve (4) is closed, and the hydraulic motor return oil is prevented from flowing into the shuttle valve (4);

finally, the return oil of the hydraulic motor flows out of the 1 st oil port (V1) after passing through the 1 st branch port (A1) and then flows into the oil return end (T) of the oil supply reversing valve (5), so that a hydraulic oil circulation loop is formed;

step 2, the hydraulic motor (7) drives the load (9) to rise to a specified height, and the load (9) is kept at the specified height, and the method comprises the following steps:

step 2.1, when the load (9) rises to a specified height, operating the oil supply reversing valve (5) to shift the oil supply reversing valve (5) to a stop gear; at this moment, the oil supply reversing valve (5) stops supplying oil to the special balance valve group of the aerial ladder vehicle, namely: hydraulic oil cannot be input into the 1 st oil port (V1) and the 2 nd oil port (V2);

step 2.2, the check valve (32) of the balancing valve (3) is closed, and since no hydraulic oil is connected to the motor brake port (6) through the oil outlet (X) of the shuttle valve (4), the hydraulic motor brake is closed, i.e.: the hydraulic motor is in a braking state;

meanwhile, since no hydraulic oil flows into the 1 st motor port (D1) and the 2 nd motor port (D2) of the hydraulic motor (7), the hydraulic motor (7) stops rotating;

therefore, when the oil supply reversing valve (5) shifts to a stop gear position, the hydraulic motor (7) stops rotating and the hydraulic motor is braked, and the load (9) is kept at a designated position by the balance valve (3);

step 3, the hydraulic motor (7) drives the winding drum (8) to rotate reversely, and under the action of the load (9), the load (9) is enabled to descend around the winding drum (8) under the working condition, namely: the load (9) is a working condition when the load is not in contact with a ground support in the descending process, and the method comprises the following steps:

step 3.1, operating the oil supply reversing valve (5) to enable the oil supply reversing valve (5) to shift to a reverse gear, wherein at the moment, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with a1 st oil port (V1) and conveys hydraulic oil to a1 st oil port (V1);

step 3.2, the hydraulic oil flows to the 1 st branch port (A1) after passing through the 1 st oil port (V1), and the 1 st branch port (A1) is divided into two paths of hydraulic oil:

the first path of hydraulic oil enters the interior of the shuttle valve (4) through a1 st oil inlet of the shuttle valve (4), pushes a valve core of the shuttle valve (4) from left to right, pushes the valve core of the shuttle valve (4) to the right, closes a2 nd oil inlet of the shuttle valve (4), blocks a 4 th branch port (B1) from supplying oil to a2 nd oil inlet of the shuttle valve (4), and simultaneously opens an oil outlet (X) of the shuttle valve (4), so that the first path of hydraulic oil flows out of the oil outlet (X) of the shuttle valve (4), flows into a motor brake cavity through a motor brake port (6), and further opens a motor brake;

meanwhile, the second path of hydraulic oil flows to a2 nd branch port (A2), the 2 nd branch port (A2) is a high-pressure side, therefore, the pilot control valve (31) is opened, and the pilot control valve (31) is enabled to establish a balanced back pressure according to the pressure applied by the load (9);

3.3, the hydraulic oil flowing out of the 2 nd branch port (A2) flows to the 3 rd branch port (A3), and since the pilot control valve (31) establishes balanced back pressure according to the pressure applied by the load (9) in the falling process of the load (9), in order to ensure that the load (9) descends in uniform speed balance, the pressure of the 5 th branch port (B2) is higher than the pressure of the 3 rd branch port (A3), and therefore the bypass one-way valve (2) is in a closed state; that is, during the falling of the load (9), the load (9) applies a dragging force to the winding drum (8), and the dragging force maintains a flat transverse through the back pressure established by the pilot control valve (31), so as to control the load (9) to fall smoothly;

step 3.4, allowing the hydraulic oil flowing out of the 3 rd branch port (A3) to flow into the hydraulic motor cavity through the 1 st motor oil port (D1) so as to drive the hydraulic motor (7) to rotate reversely; the hydraulic motor (7) rotates reversely, and the load (9) is enabled to descend uniformly under the action of gravity of the load (9);

the return oil of the hydraulic motor flows out from a2 nd motor oil port (D2), flows into a 5 th branch port (B2) from a2 nd load port (C2), flows into a 4 th branch port (B1) after passing through a pilot control valve (31), finally flows out from a2 nd oil port (V2) and flows into an oil return end (T) of an oil supply reversing valve (5), so that a hydraulic oil circulation loop is formed;

and 4, enabling the winding drum (8) to be in a release state by the hydraulic motor (7), further enabling the load (9) to descend, and once the load falls in place and falls to the ground, working conditions are as follows:

when the load falls to the right position and lands, at the moment, because the winding drum (8) is not dragged by the load (9) any more, correspondingly, the dragging force of the winding drum (8) to the hydraulic motor (7) also disappears, and accordingly, the back pressure of the pilot control valve (31) which is established according to the load (9) and is balanced disappears, so that the pressure of the 5 th branch port (B2) is immediately and rapidly reduced, the pressure of the 5 th branch port (B2) is far lower than the pressure of the 3 rd branch port (A3), therefore, the bypass check valve (2) is rapidly conducted, and because the opening pressure of the bypass check valve (2) is smaller than the no-load starting pressure of the hydraulic motor (7), the hydraulic oil flowing to the 3 rd branch port (A3) completely flows to the 5 th branch port (B2) through the bypass check valve (2) and then flows back to the oil return end (T) of the oil supply reversing valve (5) after passing through the pilot control valve (31), thereby forming a hydraulic oil circulation circuit;

that is to say, after the bypass check valve (2) is conducted, the bypass check valve (2) bypasses the hydraulic motor (7), and the hydraulic oil reaching the 3 rd branch port (A3) does not flow into the hydraulic cavity of the hydraulic motor (7), so that the hydraulic motor (7) stops rotating immediately, the effect that the hydraulic motor (7) stops rotating immediately when the load falls in place and falls to the ground is achieved, the winding drum (8) stops rotating immediately, and the steel wire rope is prevented from loosening.

Technical Field

The invention belongs to the technical field of balance valves, and particularly relates to a special balance valve group for an aerial ladder vehicle, a hydraulic control system and a control method of the hydraulic control system.

Background

The aerial ladder vehicle is used as a special engineering vehicle and is mainly used for assisting workers in transporting equipment or goods to high altitude or used for rescuing high-rise trapped people and other occasions, wherein the extension and retraction of the aerial ladder and the lifting of a trolley are realized by driving a winding drum to wind a steel wire rope through a hydraulic motor, and the aerial ladder vehicle generally acts through a manual reversing valve. Under many circumstances, when the scaling ladder or the trolley descends, when the scaling ladder or the trolley falls to the bottom and the steel wire rope does not bear the pulling force any more, the reversing valve is still in the reversing position at the moment, oil is continuously supplied, the motor still continues to rotate, the problems of loosening, winding, disorderly arrangement and the like of the steel wire rope on the winding drum are caused, and the steel wire rope is seriously clamped into a scaling ladder guide rail even to cause mechanical faults.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a special balance valve group for an aerial ladder vehicle, a hydraulic control system and a control method thereof, which can effectively solve the problems.

The technical scheme adopted by the invention is as follows:

the invention provides a special balance valve group for an aerial ladder vehicle, which comprises a valve body (1), wherein the valve body (1) is integrated with a bypass one-way valve (2), a balance valve (3) and a shuttle valve (4); the valve body (1) is provided with a1 st oil port (V1), a2 nd oil port (V2), a1 st load port (C1) and a2 nd load port (C2);

the 1 st oil port (V1) and the 2 nd oil port (V2) are both used for being connected to an oil supply reversing valve (5); the 1 st load port (C1) is used for being connected to a1 st motor port (D1) of a hydraulic motor; the 2 nd load port (C2) is used for being connected to a2 nd motor port (D2) of a hydraulic motor;

a1 st oil path is formed between the 1 st oil port (V1) and the 1 st load port (C1); a1 st branch port (A1), a2 nd branch port (A2) and A3 rd branch port (A3) are sequentially arranged on the 1 st oil passage in a direction from the 1 st oil port (V1) to the 1 st load port (C1);

a2 nd oil path is formed between the 2 nd oil port (V2) and the 2 nd load port (C2); a 4 th branch port (B1), the balance valve (3), and a 5 th branch port (B2) are provided in the 2 nd oil line in this order from the 2 nd port (V2) to the 2 nd load port (C2);

the 1 st oil inlet of the shuttle valve (4) is communicated with the 1 st branch port (A1); the 2 nd oil inlet of the shuttle valve (4) is communicated with the 4 th branch port (B1); the oil outlet (X) of the shuttle valve (4) is used for being connected to a motor brake port (6);

the oil inlet of the bypass one-way valve (2) is communicated with the 3 rd branch port (A3); an oil outlet of the bypass check valve (2) is communicated with the 5 th branch port (B2), the direction of the bypass check valve (2) from the 3 rd branch port (A3) to the 5 th branch port (B2) is a conducting direction, and the direction of the bypass check valve (2) from the 5 th branch port (B2) to the 3 rd branch port (A3) is a closing direction;

the balance valve (3) comprises a pilot control valve (31) and a one-way valve (32) which are connected in parallel; a pilot control port of the pilot control valve (31) is communicated with the 2 nd branch port (A2).

The invention also provides a hydraulic control system based on the aerial ladder vehicle special balance valve bank, which comprises the aerial ladder vehicle special balance valve bank, an oil supply reversing valve (5), a hydraulic motor (7), a winding drum (8) and a load (9);

the hydraulic driving end of the hydraulic motor (7) is connected with the winding drum (8) and is used for driving the winding drum (8) to rotate; one end of the load (9) is wound on the winding drum (8) through a steel wire rope;

the oil supply reversing valve (5) is communicated with a1 st oil port (V1) and a2 nd oil port (V2) of the aerial ladder vehicle special balance valve group; the oil supply reversing valve (5) is provided with three gears which are a forward gear, a reverse gear and a stop gear respectively; when the oil supply reversing valve (5) is reversed to a stop gear position, oil is not supplied to the 1 st oil port (V1) and the 2 nd oil port (V2); when the oil supply reversing valve (5) is reversed to a forward gear, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with the 2 nd oil port (V2) and is used for conveying hydraulic oil to the 2 nd oil port (V2); the return oil from the 1 st oil port (V1) is communicated to the oil return end (T) of the oil supply reversing valve (5); when the oil supply reversing valve (5) is reversed to a reverse gear, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with the 1 st oil port (V1) and is used for conveying hydraulic oil to the 1 st oil port (V1); the return oil passing through the 2 nd oil port (V2) is communicated to the oil return end (T) of the oil supply reversing valve (5);

an oil outlet (X) of a shuttle valve (4) of the aerial ladder vehicle special balance valve group is connected to a motor brake port (6);

the 1 st load port (C1) of the aerial ladder vehicle special balance valve bank is connected to the 1 st motor oil port (D1) of the hydraulic motor (7); the 2 nd load port (C2) is connected to the 2 nd motor port (D2) of the hydraulic motor (7);

the opening pressure of the bypass one-way valve (2) is smaller than the no-load starting pressure of the hydraulic motor (7).

The invention also provides a hydraulic control method of the hydraulic control system based on the aerial ladder vehicle special balance valve group, which comprises the following steps:

step 1, a hydraulic motor (7) drives a winding drum (8) to rotate in the positive direction, and then drives a load (9) to rise under the working condition, and the method comprises the following steps:

step 1.1, operating the oil supply reversing valve (5) to enable the oil supply reversing valve (5) to shift to a forward gear, wherein at the moment, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with a2 nd oil port (V2), and conveying hydraulic oil to the 2 nd oil port (V2);

step 1.2, the hydraulic oil flows to a 4 th branch port (B1) after passing through a2 nd oil port (V2), and the 4 th branch port (B1) is divided into two paths of hydraulic oil:

the first path of hydraulic oil enters the interior of the shuttle valve (4) through a2 nd oil inlet of the shuttle valve (4), pushes a valve core of the shuttle valve (4) from right to left, pushes the valve core of the shuttle valve (4) to the left, closes a1 st oil inlet of the shuttle valve (4), blocks a1 st branch port (A1) from supplying oil to a1 st oil inlet of the shuttle valve (4), and simultaneously opens an oil outlet (X) of the shuttle valve (4), so that the first path of hydraulic oil flows out of the oil outlet (X) of the shuttle valve (4), flows into a motor brake cavity through a motor brake port (6), and further opens a motor brake;

meanwhile, for the second path of hydraulic oil, because the 2 nd oil port (V2) is communicated with the hydraulic oil delivery end (P) of the oil supply reversing valve (5), and the 1 st oil port (V1) is communicated with the oil return end (T) of the oil supply reversing valve (5), the oil pressure of the 2 nd oil path between the 2 nd oil port (V2) and the 2 nd load port (C2) is higher than the oil pressure of the 1 st oil path between the 1 st oil port (V1) and the 1 st load port (C1), therefore, the pilot control port of the balance valve (3) is a low pressure end, the pilot control valve (31) is closed, the second path of hydraulic oil flows to the 5 th branch port (B2) through the check valve (32) of the balance valve (3), the direction from the 5 th branch port (B2) to the 1 st oil port (V1) of the bypass check valve (2) is in a closed state, therefore, the second path of hydraulic oil directly flows out from the 2 nd load port (C2) after passing through the 5 th branch port (B2), then flows into a hydraulic motor cavity through a motor oil port (D2) of the 2 nd so as to drive the hydraulic motor (7) to rotate forwards; the hydraulic motor (7) rotates forwards, so that the winding drum (8) is driven to rotate forwards, and the load (9) is driven to ascend;

the return oil of the hydraulic motor flows out from a1 st motor oil port (D1) and flows into A3 rd branch port (A3) from a1 st load port (C1); at the 3 rd branch port (A3), the oil return pressure of the 3 rd branch port (A3) is far lower than the oil supply pressure of the 5 th branch port (B2), so that the bypass check valve (2) is in a closed state;

after passing through the 3 rd branch port (A3), the hydraulic motor return oil flows to the 2 nd branch port (A2), and the pilot control valve (31) is in a closed state because the 2 nd branch port (A2) is a low-pressure end;

after passing through the 2 nd branch port (A2), the hydraulic motor return oil flows to the 1 st branch port (A1), and because the 1 st branch port (A1) is a low-pressure end and the pressure is far less than the pressure of the 4 th branch port (B1), the 1 st oil inlet of the shuttle valve (4) is closed, and the hydraulic motor return oil is prevented from flowing into the shuttle valve (4);

finally, the return oil of the hydraulic motor flows out of the 1 st oil port (V1) after passing through the 1 st branch port (A1) and then flows into the oil return end (T) of the oil supply reversing valve (5), so that a hydraulic oil circulation loop is formed;

step 2, the hydraulic motor (7) drives the load (9) to rise to a specified height, and the load (9) is kept at the specified height, and the method comprises the following steps:

step 2.1, when the load (9) rises to a specified height, operating the oil supply reversing valve (5) to shift the oil supply reversing valve (5) to a stop gear; at this moment, the oil supply reversing valve (5) stops supplying oil to the special balance valve group of the aerial ladder vehicle, namely: hydraulic oil cannot be input into the 1 st oil port (V1) and the 2 nd oil port (V2);

step 2.2, the check valve (32) of the balancing valve (3) is closed, and since no hydraulic oil is connected to the motor brake port (6) through the oil outlet (X) of the shuttle valve (4), the hydraulic motor brake is closed, i.e.: the hydraulic motor is in a braking state;

meanwhile, since no hydraulic oil flows into the 1 st motor port (D1) and the 2 nd motor port (D2) of the hydraulic motor (7), the hydraulic motor (7) stops rotating;

therefore, when the oil supply reversing valve (5) shifts to a stop gear position, the hydraulic motor (7) stops rotating and the hydraulic motor is braked, and the load (9) is kept at a designated position by the balance valve (3);

step 3, the hydraulic motor (7) drives the winding drum (8) to rotate reversely, and under the action of the load (9), the load (9) is enabled to descend around the winding drum (8) under the working condition, namely: the load (9) is a working condition when the load is not in contact with a ground support in the descending process, and the method comprises the following steps:

step 3.1, operating the oil supply reversing valve (5) to enable the oil supply reversing valve (5) to shift to a reverse gear, wherein at the moment, a hydraulic oil conveying end (P) of the oil supply reversing valve (5) is communicated with a1 st oil port (V1) and conveys hydraulic oil to a1 st oil port (V1);

step 3.2, the hydraulic oil flows to the 1 st branch port (A1) after passing through the 1 st oil port (V1), and the 1 st branch port (A1) is divided into two paths of hydraulic oil:

the first path of hydraulic oil enters the interior of the shuttle valve (4) through a1 st oil inlet of the shuttle valve (4), pushes a valve core of the shuttle valve (4) from left to right, pushes the valve core of the shuttle valve (4) to the right, closes a2 nd oil inlet of the shuttle valve (4), blocks a 4 th branch port (B1) from supplying oil to a2 nd oil inlet of the shuttle valve (4), and simultaneously opens an oil outlet (X) of the shuttle valve (4), so that the first path of hydraulic oil flows out of the oil outlet (X) of the shuttle valve (4), flows into a motor brake cavity through a motor brake port (6), and further opens a motor brake;

meanwhile, the second path of hydraulic oil flows to a2 nd branch port (A2), the 2 nd branch port (A2) is a high-pressure side, therefore, the pilot control valve (31) is opened, and the pilot control valve (31) is enabled to establish a balanced back pressure according to the pressure applied by the load (9);

3.3, the hydraulic oil flowing out of the 2 nd branch port (A2) flows to the 3 rd branch port (A3), and since the pilot control valve (31) establishes balanced back pressure according to the pressure applied by the load (9) in the falling process of the load (9), in order to ensure that the load (9) descends in uniform speed balance, the pressure of the 5 th branch port (B2) is higher than the pressure of the 3 rd branch port (A3), and therefore the bypass one-way valve (2) is in a closed state; that is, during the falling of the load (9), the load (9) applies a dragging force to the winding drum (8), and the dragging force maintains a flat transverse through the back pressure established by the pilot control valve (31), so as to control the load (9) to fall smoothly;

step 3.4, allowing the hydraulic oil flowing out of the 3 rd branch port (A3) to flow into the hydraulic motor cavity through the 1 st motor oil port (D1) so as to drive the hydraulic motor (7) to rotate reversely; the hydraulic motor (7) rotates reversely, and the load (9) is enabled to descend uniformly under the action of gravity of the load (9);

the return oil of the hydraulic motor flows out from a2 nd motor oil port (D2), flows into a 5 th branch port (B2) from a2 nd load port (C2), flows into a 4 th branch port (B1) after passing through a pilot control valve (31), finally flows out from a2 nd oil port (V2) and flows into an oil return end (T) of an oil supply reversing valve (5), so that a hydraulic oil circulation loop is formed;

and 4, enabling the winding drum (8) to be in a release state by the hydraulic motor (7), further enabling the load (9) to descend, and once the load falls in place and falls to the ground, working conditions are as follows:

when the load falls to the right position and lands, at the moment, because the winding drum (8) is not dragged by the load (9) any more, correspondingly, the dragging force of the winding drum (8) to the hydraulic motor (7) also disappears, and accordingly, the back pressure of the pilot control valve (31) which is established according to the load (9) and is balanced disappears, so that the pressure of the 5 th branch port (B2) is immediately and rapidly reduced, the pressure of the 5 th branch port (B2) is far lower than the pressure of the 3 rd branch port (A3), therefore, the bypass check valve (2) is rapidly conducted, and because the opening pressure of the bypass check valve (2) is smaller than the no-load starting pressure of the hydraulic motor (7), the hydraulic oil flowing to the 3 rd branch port (A3) completely flows to the 5 th branch port (B2) through the bypass check valve (2) and then flows back to the oil return end (T) of the oil supply reversing valve (5) after passing through the pilot control valve (31), thereby forming a hydraulic oil circulation circuit;

that is to say, after the bypass check valve (2) is conducted, the bypass check valve (2) bypasses the hydraulic motor (7), and the hydraulic oil reaching the 3 rd branch port (A3) does not flow into the hydraulic cavity of the hydraulic motor (7), so that the hydraulic motor (7) stops rotating immediately, the effect that the hydraulic motor (7) stops rotating immediately when the load falls in place and falls to the ground is achieved, the winding drum (8) stops rotating immediately, and the steel wire rope is prevented from loosening.

The special balance valve group for the aerial ladder vehicle, the hydraulic control system and the control method thereof provided by the invention have the following advantages:

according to the special balance valve group for the aerial ladder vehicle, the hydraulic control system and the control method thereof, the winding hydraulic motor loop can be timely bypassed by the specially designed bypass check valve and stops rotating after the load is in place or falls to the ground, so that the problems of looseness, winding and the like of a steel wire rope caused by idling of a winding drum connected with a hydraulic motor are avoided, and the use safety and reliability of the winding drum are ensured.

Drawings

Fig. 1 is a schematic structural diagram of a principle of a special balance valve bank for an aerial ladder vehicle provided by the invention;

FIG. 2 is a schematic diagram of a hydraulic control system according to the present invention;

fig. 3 is a perspective view of the special balance valve bank for an aerial ladder vehicle provided by the invention at an angle;

fig. 4 is a perspective view of the special balance valve bank for an aerial ladder vehicle provided by the invention at an angle;

fig. 5 is a perspective view of the special balance valve set for the aerial ladder vehicle provided by the invention at an angle;

fig. 6 is a cross-sectional view of the special balance valve set for the aerial ladder vehicle provided by the invention at an angle;

fig. 7 is a cross-sectional view of the special balance valve set for the aerial ladder vehicle provided by the invention at an angle.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a special balance valve group for an aerial ladder vehicle, a hydraulic control system and a control method thereof, which can realize that a winding hydraulic motor loop is timely bypassed by a specially designed bypass one-way valve and stops rotating after a load is in place or falls to the ground, thereby avoiding the problems of loosening and winding of a steel wire rope caused by the idle running of a winding drum connected with a hydraulic motor, and ensuring the use safety and reliability of the winding drum.

Referring to fig. 1, fig. 3, fig. 4, fig. 5, fig. 6 and fig. 7, the special balance valve set for the aerial ladder vehicle provided by the invention comprises a valve body 1, wherein the valve body 1 is integrated with a bypass check valve 2, a balance valve 3 and a shuttle valve 4; the valve body 1 is provided with a1 st oil port V1, a2 nd oil port V2, a1 st load port C1 and a2 nd load port C2;

the 1 st port V1 and the 2 nd port V2 are both used for being connected to the oil supply reversing valve 5; the 1 st load port C1 is for connection to the 1 st motor port D1 of the hydraulic motor; the 2 nd load port C2 is for connection to the 2 nd motor port D2 of the hydraulic motor;

a1 st oil path is formed between the 1 st oil port V1 and the 1 st load port C1; a1 st branch port a1, a2 nd branch port a2 and A3 rd branch port A3 are sequentially provided in the 1 st oil passage in the direction from the 1 st port V1 to the 1 st load port C1;

a2 nd oil passage is formed between the 2 nd oil port V2 and the 2 nd load port C2; a 4 th branch port B1, a balance valve 3 and a 5 th branch port B2 are sequentially arranged on the 2 nd oil path in the direction from the 2 nd port V2 to the 2 nd load port C2;

a1 st oil inlet of the shuttle valve 4 is communicated with a1 st branch port A1; the 2 nd oil inlet of the shuttle valve 4 is communicated with a 4 th branch port B1; the oil outlet X of the shuttle valve 4 is used for being connected to the motor brake port 6;

an oil inlet of the bypass check valve 2 is communicated with a3 rd branch port A3; an oil outlet of the bypass check valve 2 is communicated with a 5 th branch port B2, the direction of the bypass check valve 2 from the 3 rd branch port A3 to the 5 th branch port B2 is a conducting direction, and the direction of the bypass check valve 2 from the 5 th branch port B2 to the 3 rd branch port A3 is a closing direction;

the balance valve 3 includes a pilot control valve 31 and a check valve 32 connected in parallel; the pilot control port of the pilot control valve 31 is communicated to the 2 nd branch port a 2.

By applying the special balance valve group for the aerial ladder vehicle, which is provided by the figure 1, and referring to the figure 2, the invention also provides a hydraulic control system based on the special balance valve group for the aerial ladder vehicle, which comprises the special balance valve group for the aerial ladder vehicle, an oil supply reversing valve 5, a hydraulic motor 7, a winding drum 8 and a load 9;

the hydraulic driving end of the hydraulic motor 7 is connected with the winding drum 8 and is used for driving the winding drum 8 to rotate; one end of a load 9 is wound on the winding drum 8 through a steel wire rope;

the oil supply reversing valve 5 is communicated with a1 st oil port V1 and a2 nd oil port V2 of the special balance valve group for the aerial ladder vehicle; the oil supply reversing valve 5 is provided with three gears which are a forward gear, a reverse gear and a stop gear respectively; when the oil supply reversing valve 5 is reversed to a stop gear position, oil is not supplied to the 1 st oil port V1 and the 2 nd oil port V2; when the oil supply reversing valve 5 is reversed to a forward gear, a hydraulic oil conveying end P of the oil supply reversing valve 5 is communicated with the 2 nd oil port V2 and is used for conveying hydraulic oil to the 2 nd oil port V2; the return oil from the 1 st oil port V1 is communicated to the oil return end T of the oil supply reversing valve 5; when the oil supply reversing valve 5 is reversed to a reverse gear, a hydraulic oil delivery end P of the oil supply reversing valve 5 is communicated with the 1 st oil port V1 and is used for delivering hydraulic oil to the 1 st oil port V1; the return oil from the 2 nd oil port V2 is communicated to the oil return end T of the oil supply reversing valve 5;

an oil outlet X of a shuttle valve 4 of the special balance valve group for the aerial ladder vehicle is connected to a motor brake port 6;

the 1 st load port C1 of the aerial ladder vehicle special balance valve bank is connected to the 1 st motor port D1 of the hydraulic motor 7; the 2 nd load port C2 is connected to the 2 nd motor port D2 of the hydraulic motor 7;

the opening pressure of the bypass check valve 2 is smaller than the no-load starting pressure of the hydraulic motor 7.

The invention provides a hydraulic control method of a hydraulic control system based on a special balance valve group for an aerial ladder vehicle, which comprises the following steps:

step 1, the hydraulic motor 7 drives the winding drum 8 to rotate in the forward direction, and further drives the load 9 to rise under the working condition, and the method comprises the following steps:

step 1.1, operating the oil supply reversing valve 5 to shift the oil supply reversing valve 5 to a forward gear, wherein at the moment, a hydraulic oil conveying end P of the oil supply reversing valve 5 is communicated with a2 nd oil port V2, and conveying hydraulic oil to a2 nd oil port V2;

step 1.2, the hydraulic oil flows to a 4 th branch port B1 after passing through a2 nd oil port V2, and the hydraulic oil is divided into two paths of hydraulic oil at the 4 th branch port B1:

the first path of hydraulic oil enters the interior of the shuttle valve 4 through the 2 nd oil inlet of the shuttle valve 4, pushes the valve core of the shuttle valve 4 from right to left, pushes the valve core of the shuttle valve 4 to the left, closes the 1 st oil inlet of the shuttle valve 4, blocks the 1 st branch port A1 from supplying oil to the 1 st oil inlet of the shuttle valve 4, and simultaneously opens the oil outlet X of the shuttle valve 4, so that the first path of hydraulic oil flows out of the oil outlet X of the shuttle valve 4 and flows into a motor brake cavity through the motor brake port 6, and further opens the motor brake;

meanwhile, for the second path of hydraulic oil, since the 2 nd oil port V2 is communicated with the hydraulic oil delivery end P of the oil supply reversing valve 5, the 1 st oil port V1 is communicated with the oil return end T of the oil supply reversing valve 5, therefore, the oil pressure of the 2 nd oil passage between the 2 nd port V2 and the 2 nd load port C2 is higher than the oil pressure of the 1 st oil passage between the 1 st port V1 and the 1 st load port C1, therefore, the pilot control port of the balancing valve 3 is a low pressure side, the pilot control valve 31 is closed, the second hydraulic oil flows to the 5 th branch port B2 through the check valve 32 of the balancing valve 3, since the direction from the 5 th branch port B2 to the 1 st port V1 of the bypass check valve 2 is in the closed state, therefore, after passing through the 5 th branch port B2, the second path of hydraulic oil directly flows out of the 2 nd load port C2, and then flows into the hydraulic motor cavity through the 2 nd motor port D2, and further drives the hydraulic motor 7 to rotate in the forward direction; the hydraulic motor 7 rotates in the positive direction, so that the winding drum 8 is driven to rotate in the positive direction, and the load 9 is driven to ascend;

the return oil of the hydraulic motor flows out from the 1 st motor port D1, and flows into the 3 rd branch port A3 from the 1 st load port C1; at the 3 rd branch port A3, the return oil pressure at the 3 rd branch port A3 is much lower than the supply oil pressure at the 5 th branch port B2, and therefore the bypass check valve 2 is in a closed state;

after passing through the 3 rd branch port A3, the hydraulic motor return oil flows to the 2 nd branch port a2, and the pilot control valve 31 is in a closed state because the 2 nd branch port a2 is a low-pressure end;

after passing through the 2 nd branch port A2, the hydraulic motor return oil flows to the 1 st branch port A1, and because the 1 st branch port A1 is a low-pressure end and the pressure is far less than the pressure of the 4 th branch port B1, the 1 st oil inlet of the shuttle valve 4 is closed, and the hydraulic motor return oil is prevented from flowing into the shuttle valve 4;

finally, the return oil of the hydraulic motor flows out of the 1 st branch port V1 after passing through the 1 st branch port a1, and then flows into the oil return end T of the oil supply reversing valve 5, thereby forming a hydraulic oil circulation loop;

step 2, the hydraulic motor 7 drives the load 9 to rise to the designated height, and the load 9 is kept in the working condition of the designated height, and the method comprises the following steps:

step 2.1, when the load 9 rises to a specified height, operating the oil supply reversing valve 5 to enable the oil supply reversing valve 5 to shift to a stop gear; at this moment, the oil supply reversing valve 5 stops supplying oil to the special balance valve group of the aerial ladder vehicle, namely: hydraulic oil cannot be input to the 1 st port V1 and the 2 nd port V2;

step 2.2, the check valve 32 of the balance valve 3 is closed, and since no hydraulic oil is connected to the motor brake port 6 through the oil outlet X of the shuttle valve 4, the hydraulic motor brake is closed, that is: the hydraulic motor is in a braking state;

meanwhile, since no hydraulic oil flows into the 1 st and 2 nd motor ports D1 and D2 of the hydraulic motor 7, the hydraulic motor 7 stops rotating;

therefore, when the oil supply switching valve 5 is shifted to the stop position while stopping the rotation of the hydraulic motor 7 and braking the hydraulic motor, the load 9 is held at a prescribed position by the balance valve 3;

step 3, the hydraulic motor 7 drives the winding drum 8 to rotate reversely, and under the action of the load 9, the load 9 is enabled to descend around the winding drum 8 under the working condition, namely: the load 9 is a working condition when the load is not in contact with a ground support in the descending process, and the method comprises the following steps:

step 3.1, operating the oil supply reversing valve 5 to shift the oil supply reversing valve 5 to a reverse gear, wherein at the moment, a hydraulic oil conveying end P of the oil supply reversing valve 5 is communicated with the 1 st oil port V1 to convey hydraulic oil to the 1 st oil port V1;

step 3.2, the hydraulic oil flows to the 1 st branch port A1 after passing through the 1 st oil port V1, and the 1 st branch port A1 is divided into two paths of hydraulic oil:

the first path of hydraulic oil enters the interior of the shuttle valve 4 through the 1 st oil inlet of the shuttle valve 4, pushes the valve core of the shuttle valve 4 from left to right, pushes the valve core of the shuttle valve 4 to the right, closes the 2 nd oil inlet of the shuttle valve 4, blocks the 4 th branch port B1 from supplying oil to the 2 nd oil inlet of the shuttle valve 4, and simultaneously opens the oil outlet X of the shuttle valve 4, so that the first path of hydraulic oil flows out of the oil outlet X of the shuttle valve 4 and flows into the motor brake cavity through the motor brake port 6, and further opens the motor brake;

meanwhile, the second hydraulic oil flows to the 2 nd branch port a2, and the 2 nd branch port a2 is a high pressure side, so that the pilot control valve 31 is opened, and the pilot control valve 31 establishes a balanced back pressure according to the pressure applied by the load 9;

3.3, the hydraulic oil flowing out of the 2 nd branch port A2 flows to the 3 rd branch port A3, and since the pilot control valve 31 establishes a balanced back pressure according to the pressure applied by the load 9 during the falling of the load 9, in order to ensure that the load 9 descends in a uniform balanced manner, the pressure of the 5 th branch port B2 is higher than the pressure of the 3 rd branch port A3, and therefore the bypass check valve 2 is in a closed state; that is, during the falling of the load 9, the load 9 applies a dragging force to the drum 8, which is maintained to be level by the back pressure established by the pilot control valve 31, thereby controlling the load 9 to fall smoothly;

step 3.4, the hydraulic oil flowing out of the 3 rd branch port A3 flows into the hydraulic motor cavity through the 1 st motor oil port D1, and then drives the hydraulic motor 7 to rotate reversely; the hydraulic motor 7 rotates reversely, and the load 9 descends uniformly under the action of the gravity of the load 9;

the hydraulic motor return oil flows out from the 2 nd motor oil port D2, flows into the 5 th branch port B2 from the 2 nd load port C2, flows into the 4 th branch port B1 through the pilot control valve 31, flows out from the 2 nd oil port V2, and flows into the return oil port T of the oil supply reversing valve 5, thereby forming a hydraulic oil circulation circuit;

step 4, the hydraulic motor 7 makes the winding drum 8 in a release state, so that the load 9 descends, and once the load falls in place and falls to the ground, the working conditions are as follows:

when the load falls to the right position and falls to the ground, at this time, because the winding drum 8 is not dragged by the load 9 any more, correspondingly, the dragging force of the winding drum 8 to the hydraulic motor 7 also disappears, therefore, the back pressure of the phase balance established by the pilot control valve 31 according to the load 9 disappears, thereby immediately causing the pressure of the 5 th branch port B2 to rapidly drop, causing the pressure of the 5 th branch port B2 to be far lower than the pressure of the 3 rd branch port A3, therefore, rapidly conducting the bypass check valve 2, and because the opening pressure of the bypass check valve 2 is smaller than the idle-load starting pressure of the hydraulic motor 7, therefore, the hydraulic oil flowing to the 3 rd branch port A3 completely flows to the 5 th branch port B2 through the bypass check valve 2, then flows back to the oil return end T of the oil supply reversing valve 5 after passing through the pilot control valve 31, thereby forming a hydraulic oil circulation loop;

that is to say, after the bypass check valve 2 is turned on, the bypass check valve 2 bypasses the hydraulic motor 7, and the hydraulic oil reaching the 3 rd branch port a3 does not flow into the hydraulic cavity of the hydraulic motor 7 any more, so that the hydraulic motor 7 immediately stops rotating, and when the load falls in place and lands, the hydraulic motor 7 immediately stops rotating, so that the winding drum 8 immediately stops rotating, and the steel wire rope is prevented from loosening.

In conclusion, the invention provides the special balance valve group for the aerial ladder vehicle, the hydraulic control system and the control method thereof, which can realize that after a load is in place or falls to the ground, a winding hydraulic motor loop is timely bypassed by a specially designed bypass one-way valve and stops rotating, so that the problems of loosening and winding of a steel wire rope caused by idle running of a winding drum connected with a hydraulic motor are avoided, and the use safety and reliability of the winding drum are ensured.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and improvements can be made without departing from the principle of the present invention, and such modifications and improvements should also be considered within the scope of the present invention.